Power-operated cloth folding apparatus



Oct. 20, 1970 w. L. LYNCH, JR 3,534,954

POWER-OPERATED CLOTH FOLDING APPARATUS Filed Oct. 25, 1968 4 Sheets-51mm 1 FIOI DRIVE SYNCHRONIZEO WITH CLOTH WORK PIECE CONVEYOR INVENTOR FIGS Oct. 20, 1970 w. LYNCH, JR 3,534,954

POWER-OPERATED CLOTH FOLDING APPARATUS Filed Oct. 25, 1968 4 Sheets-Sheet 2 FIG .4

Oct. 20, 1970 w, LYNCH, JR 3,534,954

POWER-OPERATED CLOTH FOLDING APPARATUS Filed Oct. 25, 1 968 4 Sheets-Sneet 3 Oct. 20, 1970 w. L. LYNCH, JR 3,534,954

POWER-OPERATED CLOTH FOLDING APPARATUS Filed Oct. 23, 1968 4 Sheets-Sneet 4 Patented Oct. 20, 1970 3,534,954 POWER-OPERATED CLOTH FOLDING APPARATUS Walter L. Lynch, In, Greenville, S.C., assignor to Stone Manufacturing Company, Greenville, S.C., a corporation of South Carolina Filed Oct. 23, 1968, Ser. No. 769,939 Int. Cl. B6511 45/22; Db 35/02 US. Cl. 270-93 5 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION A definite need has existed for some time for a practical and reliable power folder or hemmer to be used in conjunction with a sewing machine for substantially automatically hemming garment components, towels or like cloth articles. At the present time, no entirely satisfactory apparatus for this purpose has been devised. Certain aids to hand folding have been proposed in the prior art to reduce manual labor involved and also the skill and time required to some extent. However, these devices are not adequate to meet the requirements of automation systems which are presently coming into being in the industry. It is the aim of the invention to satisfy this need with a relatively simple, reliable and economical self-contained attachment or unit which can be adapted to a variety of folding or hemming situations in a manufacturing facility. The necessary adjustments are included to render the apparatus versatile.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view, partly broken away, of a cloth folding apparatus embodying the invention.

FIG. 2 is a side elevational view of the apparatus in FIG. 1.

FIG. 3 is an enlarged side elevation, partly in section, of a cloth feeding and timing means.

FIG. 4 is an enlarged transverse vertical section taken on line 4-4 of FIG. 2.

FIG. 5 is a similar section taken on line 55 of FIG. 2.

FIG. 6 is an enlarged fragmentary plan view of the apparatus components which produce gradually the double fold hem, parts omitted and parts shown in section for clarity.

FIG. 7 is an exploded perspective view of cloth forming or folding elements.

FIG. 8 is an enlarged fragmentary transverse vertical section taken on line 88 of FIG. 1.

FIGS. 9 through 15 are similar sectional views taken on the correspondingly numbered section lines 9 through 15 of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings in detail, wherein like numerals designate like parts, and referring first to FIGS. 1 and 2 showing the assembled apparatus substantially in its entirety, the numeral 20 designates a main horizontal bed plate over which the cloth moves while being subjected to the folding or hemming operation in the apparatus. The bed plate 20 is secured rigidly to an underlying block 21 by means of screws 20' and this block in turn rests upon a horizontal ledge 22 of a first elongated cloth folding member or bar 23, to be described in greater detail. The ledge 22 is seated on a main mounting bracket or plate structure 24 which may carry a depending adapter shaft 25 rigid therewith and engageable with a further supporting structure, not shown. The parts 21, 22 and 24 are suitably detachably interconnected so that they may be separated when required. The details of mounting or attaching the apparatus unit to a particular basic support may be varied considerably according to needs without effecting the basic components of the invention and the mode of operation for folding or hemming cloth articles.

Near the outer longitudinal side of the bed plate 20, a cloth feeding and timing assembly 26 is arranged including a frame member 27 around which a flexible toothed timing belt 28 passes. The frame 26 is carried by a horizontal arm 29, FIG. 5, pivoted at 30 to a post element 31 which is vertically adjustable supported as at 32 relative to the mounting bracket 24. The arm 29 and frame 27 may be lifted bodily around the axis of pivot 30 so as to raise the feeding and timing assembly from the bed plate 20 at certain times. An adjustable stop screw means 33 on the arm 29 contacts the mounting bracket 24 to assure proper placement of the frame 27 relative to the bed plate 20 when the feeding assembly is returned to its normal cloth feeding position shown in FIG. 5.

Upstream from the power feeding assembly is a pre liminary sheet metal cloth former 34 secured adjustably at 35 and 36 to the main bed plate 20 which extends thereunder at 37, FIG. 1. A gage bar 38 having a straight edge 39 extends further upstream from the former 34 for preliminary guiding of the edge of the cloth into the former 34. The bar '38 may rest upon bottom wall 40 of the former 34 and the bar may be secured adjustably by the fastener means 36. A small air jet nozzle means 41 is preferably provided near the inlet end of the former 34 to nudge the cloth toward the straight edge 39 and into the former which includes a top wall 42 lying above the bottom wall 40. The sheet metal former 34 in general is an elongated folded structure which simply guides and forms the cloth piece into the proper preliminary shape to lead into the power feeding and timing assembly and the underlying folding and forming components shown in FIG. 5 and in FIGS. 8 through 15, as well as in FIGS. 6 and 7.

These final folding components include the previouslymentioned longitudinal folding bar 23 and a companion bar 43 at one side thereof, as shown in FIG. 5. The peculiar cross sectional shapes of these elements will be described, particularly in connection with FIGS. 8 through 15 as the description proceeds. The bar 43 is also suitably seated with respect to the mounting bracket 24 and these details are omitted from the drawings for clarity. The folding or forming bars 23 and 43 are also shown in assembled relationship in FIG. 6 of the drawings.

Still another major component necessary to the complete formation of the desired double fold hem resides in an elongted sheet metal tongue element 44 which lies above and parallel to the plane of the top forming face 45 of bar 23, which face has its transverse angle of inclination consantly changing along what might be termed a spiral path. This constant change of inclination for the face 45 and tongue element 44, spaced closely adjacent to it, is clearly evident from an inspection of FIGS. 5 and 10 through 15. The tongue element 44 is a narrow strip which may be unsupported for the major portion of its active length, but includes a wider base extension 46,

3 FIG. 6, which is horizontal and suitably secured at 47 to the bottom of bed plate 20. The tongue has a short connecting portion 48 where the transition from horizontal to lateral inclination takes place and from this point downstream, the tongue has its inclination constantly changing on a spiral path, as explained for the forming surface 45.

The final important cloth forming element is a relatively small contoured rigid plate 49 which is secured by screws 50 to the vertical edge face 51 of the forming bar 23. This plate element 49 has an upper curved lip 52 whose curvature increases gradually toward its downstream end, as shown particularly in FIGS. 11 and 12. The plate 49 is mounted near the inlet or upstream end of the other folding components 23, 44 and 43, as most clearly shown in FIG. 6. The coaction among these elements in conjunction with the cloth feeding or advancing means 26 will be fully described.

Referring further to the cloth feeding and timing as sembly 26, this assembly includes toothed gears 53 and 54 at the ends of the belt guide frame 27, said gears being adjustably mounted on the frame as by supporting arms 55 and 56 shown in FIG. 3. The gear 53, FIG. 4, is driven by a transverse shaft 57 connected with a bevel gear drive 58 spaced from the outside of the apparatus. A depending input shaft 59 from this bevel gear unit is suitably driven so that the feeding belt 28 will be synchronized with the clothworkpiece conveyor belts 60 shown partially in broken lines in FIGS. 1 and 2. These belts 60 are conventional and form a continuously moving bed for the cloth workpieces which are placed on the conveyor belt upstream from the power folding apparatus, either manually or automatically. The entire cloth article is therefore supported as its edge portion to be hemmed moves first into the pre-former 34 and subsequently into the final folding components 23, 43, 44 and 49 adjacent the feeding assembly belt 28 whose lower run moves in the same direction as the conveyor belts 60 and at the same speed as these belts.

As shown in FIG. 5, the frame 27 is grooved at 61 to further guide the belt 28 and the lower run of the belt on the frame 27 traverses an undercut ledge 62 of main bed plate 20 in closely spaced relation thereto above the tongue 44 and forming surface 45 and associated elements. The lower run of the timing and feeding belt is backed up by a plurality of spring-loaded shoes or segments 63 whose purpose is to maintain pressure downwardly on the lower run of the timing belt. These shoes 63 may independently yield upwardly to allow irregularities in the cloth to pass under the belt without releasing the pressure ont he cloth at other points along the belt, as it is essential that the movement of the cloth remain synchronized with the conveyor means 60. Each individual shoe 63 is pivoted at its center to an element 64 carried by a vertically movable pin 65 received in a bore 66 formed in the bottom of frame member 27. The opposite ends of each shoe 63 are spring-loaded downwardly by coil springs 67. Each pin 65 carries an upper cros pin 68 whose ends project into openings 69 formed transversely through the frame 27, thus retaining the pins 65 floatingly upon the frame and rendering the shoes 63 self-adjusting to accommodate cloth irregularities smoothly.

Also mounted upon one side of the frame 27, FIG. 1, is a bracket 70 supporting a light bulb 71 above and in alignment with a photoelectric cell 72 adjustably mounted on the bed plate 20 through a longitudinal slot 73 and fastener means 74, FIG. 6. Light from the bulb 71 above the bed plate 20 and moving cloth shines on the photoelectric cell 72 which is below the bed plate 20 by passing through a slot 75 in the bed plate. When the leading edge of the cloth interupts the passage of light through the photocell, conventional circuitry will dictate to a sewing machine 76. FIG. 1, immediately downstream from the power folder, to begin stitching the double folded hem produced by the invention apparatus.

One adidtional cloth folding component in the form of a thin plate 77 is secured directly to the lower face of the main bed plate 20 by screws 78, see FIGS. 4 and 6. The upstream end 79 of this plate begins at the end of the element 49, FIG. 6, and the plate 77 extends to the dis charge end of the apparatus near the sewing machine 76. Its longitudinal edge 80 overlies the tongue 44 and includes a long diagonal section 81 crossing the tongue as viewed in FIG. 6. This diagonal edge portion gradually leads into the full width edge 80 and this gradual development of the plate 77 is clearly depicted in FIGS. 13 to 15. The plate 77, which is very thin, is in effect sandwiched in between the block 21 and the bed plate 20, FIG. 1

The outside forming bar 43 has a diagonal entrance portion 82 to assist in guiding and transferring the cloth from the downstream end of pre-former 34 into engagement with the final forming or folding components and feeding and timing means already described. Immediately in advance of the portion 82 and a diagonal inlet end portion 83 of bar 23, the pre-former 34 has its folded outer side gradually downturned as at 84, FIG. 8, and gradually directed inwardly somewhat as shown in FIG. 1 so as to position the edge portion of the cloth for the first of the folding steps, which steps are depicted in sequence in FIGS. 8 through 15.

SUMMARY OF OPERATION Referring primarily to FIGS. 8 through 15, the cloth is indicated in these views by the character C. The main body of the cloth is continually supported on the bed plate 20 and on the conveyor belts 60 immediately inwardly of the invention apparatus. The one edge portion of the cloth to be folded and hemmed is initially nudged by the air jet from nozzle 41 toward the straight edge 39 of guide bar 38 and into the folded pre-former 34 and through the same.

Upon reaching the downturned somewhat diagonal section 84 of the pre-former, the edge portion 85 of cloth, FIG. 8, will begin to be turned downwardly and immediately thereafter the cloth will enter beneath the lower run of belt 28 for positive feeding over the bed plate 20 while the belts 60 continue to move at the same speed. Substantially simultaneously, the entrance guide portion 82 of folder element 43 will guide the edge portion 85 of the cloth to a fully downturned or hanging condition, FIG. 9, between the bar 43 and the most abruptly angled section of the tongue 44 immediately following the base portion 46 thereof. The belt 28 will now be engaging the cloth C and feeding it along the ledge 62 of bed plate 20 continuously. Immediately following this, the hanging cloth edge portion 85 will encounter the diagonal inlet ramp section 83 of forming bar 23 and this will guide the cloth edge portion 85, FIG. 10, onto the widest inclined section of the continuously changing forming face 45 and under the parallel forming tongue 44, thus beginning the first actual folding of the cloth.

Following this, FIG. 11, the cloth edge portion 85 will encounter the plate 49 at a narrower portion of the surface 45 and the lip 52 of plate 49 will gradually fold over the edge portion of cloth and, in effect, fold it about the lower and upper sides of the tongue 44 as shown in FIG. 12. The steepness of slope of the forming surface 45 and tongue 44 is now decreasing somewhat toward a horizontal parallel relationship and the belt 28 is continuing to feed the cloth forwardly.

After passing beyond the plate 49, the cloth encounters the diagonal edge 81 of thin plate 77, FIG. 13 and FIG. 14, and again the tongue 44 and the forming surface 45 are becoming more nearly horizontal. The plate 77 in effect assures that the now folded edge portion of cloth is held in place around the upper side of the tongue and the tongue itself is necessary in the apparatus to provide a continuous element for the cloth to be formed or folded around in producing the double fold hem.

Finally, as shown in FIG. 15, substantially at the discharge end of the apparatus near the sewing machine 76,

the elements 23 and 43, FIG. 7, have narrowed down to rather shallow extensions 86 and 87 and the belt 28 is still active on the cloth and the forming surface 45 and coacting tongue 44 are now parallel and horizontal and the folding of the hem is completed. The full width edge 80 of the thin plate 77 is present above the horizontal tongue 44 to maintain the fold and the bed plate is still supporting the upper horizontal layer of the cloth. While in this double folded configuration, the hem emerges from beneath the belt 28, FIG. 1, and passes beyond the downstream end 88 of bed plate 20 and the stitching of the hem by the sewing machine 76 takes place.

Thus, to summarize, the actual folding of the hem requires the timed coaction of the feeding belt 28, preformer 34, bed plate 20, forming elements or bars 21 and 43, tongue 44, short plate 49 and thin plate 77, all contributing in the folding operation sequentially as described in action FIGS. 8 through 15.

The mode of operation, the structure, and the advantages of the invention in a high speed system should now be readily apparent to those skilled in the art.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or scope of the subjoined claims.

I claim:

1. Apparatus for folding flexible sheet material comprising means to support, convey and guide the material to a folding mechanism, said means including a moving conveyor belt for the material upstream from the folding mechanism, a folding mechanism comprising a bed plate receiving the material from said means, power means engaging the material above the bed plate and feeding it therealong as folding of the material occurs, the power means including an endless timing belt whose lower run contacts the material and is synchronized with the movement of said conveyor belt and extends substantially along the folding mechanism in continuous contact with the material during the folding thereof, an elongated bar having a laterally inclined upper folding surface which is substantially flat at any given point along the length of the bar, the degree of lateral inclination of said surface lessening gradually toward the material discharge end of the apparatus, said laterally inclined upper folding surface disposed below the elevation of said bed plate, a tongue element disposed above said upper folding surface and below the bed plate and being in the form of a thin plate element which is substantially flat at any small region along its length and parallel to said upper folding surface along the length of the latter, said tongue element being laterally inclined and paralleling the inclination of the upper folding surface at all points along the latter, coacting forming means under the bed plate engaging an edge portion of the material as it is fed along the bed plate and gradually folding the material over the top of the tongue element and maintaining the material so folded until the folded material emerges from the discharge end of the apparatus.

2. The apparatus of claim 1 wherein the coacting forming means comprises a relatively short upstanding forming plate at one side of the bar member near the material inlet end thereof and projecting above the laterally inclined surface of the bar member and having an upper curved tip which projects progressively further across the inclined surface of the bar member longitudinally toward the discharge end of the apparatus, and a thin substantially level plate element immediately above the tongue element to hold material folded over the top of the tongue element.

3. The apparatus of claim 2, wherein said thin plate element has a longitudinal edge which extends progressively further across the tongue element longitudinally toward the apparatus discharge end, the thin plate element disposed immediately downstream of the forming plate.

4. Apparatus for folding flexible sheet material comprising means to support, convey and guide the material to a folding mechanism, a folding mechanism comprising a bed plate receiving the material from said means, power means engaging the material above the bed plate and feeding it long the bed plate as folding of the material takes place, a laterally inclined folding surface member beneath the bed plate gradually changing along its length and along the direction of feeding of the material to a substantially horizontal surface, a tongue element above the folding surface member and beneath the bed plate and also being laterally inclined and paralleling the inclination of the folding surface member along the length of the latter, coacting forming means under the bed plate engaging an edge portion of the material as it is fed along the bed plate and gradually folding the material over the top of the tongue element and maintaining the material so folded substantially until the material emerges from the discharge end of the apparatus, and supporting means for said power means pivoted to a fixed structure so that the power means can be bodily raised and lowered relative to the bed plate, and adjustable stop means on the supporting means engageable with the fixed structure to assure returning of the power means consistently to an active position relative to the bed plate.

5. Apparatus for folding flexible sheet material comprising means for supporting and advancing said sheet material generally horizontally in one direction, a preformer receiving said advancing material and guiding it and gradually directing one longitudinal edge portion of the material downwardly, final folding means downstream from the pre-former comprising a stationary bed plate, a moving feed element for the sheet material above the bed plate and material and positively feeding the material along the bed plate, a tongue element beneath the bed plate and moving feed element and being laterally inclined and gradually decreasing in inclination along its length toward a substantially horizontal disposition at the discharge end of the apparatus, a coacting forming bar beneath the tongue element and having a laterally inclined forming face substantially parallel to the tongue element at all points therealong, a relatively short upstanding forming element at one side of the forming bar and extending for a relatively short distance only along the tongue element and forming bar near the upstream ends thereof, a substantially horizontal plate element downstream of the upstanding forming element intervened between the tongue element and bed plate to maintain an edge portion of said sheet material folded around the tongue element upon completion of said folding by the coaction of said moving feed element, bed plate, forming face, tongue element and upstanding forming element.

References Cited UNITED STATES PATENTS 639,413 12/1899 Loeb 270-93 2,236,252 3/1941 Spangler 270-93 2,483,138 9/ 1949 Helmer.

2,772,088 11/1956 Nelson 270-93 3,262,409 7/1966 Tucci 112-147 3,463,482 8/1969 Baron et a1 112-l47 XR 3,481,292 12/1969 Danahy l12l21.15

FOREIGN PATENTS 6,717,655 7/1968 Netherlands.

H. HAMPTON HUNTER, Primary Examiner US. Cl. X.R. 

